Toolholder



T. E. FRISCO July 5, 1949.

TOOLHOLDER 2 Sheets-Sheet 1 Filed July 21, 1944 INVENTOR. THEODQEE 5 FRISCO W fwd/w ATTOEAAEYS y? "r. E. FRISCO 2,475,385

TOOL HOLDER Filed July 21, 1944 2 Sheets-Sheet 2 v IN V EN TOR. THEODOEE E- FE/SCO ATTORNEYS Patentecl July 5, 1949 UNITED STATES PATENT OFFICE 2 Claims.

The present invention relates to a floating tool holder.

The principal object of this invention is to support a tool for floating or hunting movement, including both annular deviation and lateral offset of the tool axis with respect to the support axis in any direction, and to firmly secure the tool in position for operation without interfering with either the angular deviation or the lateral offset which it may have selected. Another object is to support a tool for angular and lateral hunting movement and to prevent chattering when the tool is in use.

Other objects and advantages of the invention will appear from the following detailed description of preferred embodiments.

In the accompanying drawings:

Fig. 1 is a longitudinal central sectional view of the holder and a fragmentary portion of the shank;

Fig. 2 is an exploded view of the several parts thereof;

Fig. 3 is a section of a longitudinal modification;

Fig. 4 is a similar section of a further modification;

Fig. 5 is a similar section of another modification; and

Fig. 6 is a similar section of another modification.

Referring to Figs. 1 and 2 of the drawing, the shank I may be fixed in position on any suitable support, such as the tail stock of a lathe. As shown in Fig. 1 the inner end of the shank I is threaded into one end of the barrel 2. sembled within the barrel 2 are a socket member 3, a ball 4, and a tool holder 5 formed with a socket member 6. The socket member 3 is formed with a transverse rib I and has a recess 8 in its opposite face to engage the ball 4. The rib I extends into a transverse slot 9 formed in the inner end of the shank I. The rib l is narrower than the slot 9, and the member 3 is smaller in diameter than the barrel 2, permitting universal radial movement of the member 3 with respect to the shank I. On its opposite face the socket member 3 is formed with a pair of lugs IE! which extend into notches I I formed in the socket member 6 carried by the tool holder 5. The lugs III are narrower and shorter than the notches I I to permit universal angular movement of the tool holder 5.

The foregoing parts, assembled as shown in Fig. 1, constitute a floating universal joint. Rel- I is prevented by the rib I and the lugs III. The tool holder 5 may be tilted in any direction with respect to the axis of the shank I by reason of the engagement of the sockets 3 and 5 with the ball 4. The axis of the tool holder 5 may be offset with respect to the shank axis by radial movement of the socket member 3 on the inner end of the shank I.

The socket member 6 is formed at its end with a recess I2 to engage the ball 4, and also with a convex, substantially spherical surface I3. A ring I surrounds the socket member 6 and is formed with a concave, substantially spherical surface I5 engaging the surface I3. The opposite face IB of the ring I4 engages a shoulder I! on the interior of the barrel 2. The ring I4 is smaller in diameter than the interior of the barrel 2, permitting universal radial movement of the ring with respect to the barrel. The shoulder I! is preferably of suficient radial length to remain in contact with the face I5 of the ring I4 in all positions of the ring.

Beyond the shoulder I! the barrel 2 has a counterbore I8 terminating in an inturned flange 19. A retainer ring 20, smaller in diameter than the counterbore I8, fits around the tool holder 5 and slidably engages the flange I9 so as to close the end of the barrel without preventing either angular or lateral movement of the tool holder 5. A spring 2I engages the retainer ring 20 and the face It of the ring I4, serving to hold the retainer ring against the flange I9 and to press the ring I4, the socket member 5, the ball 4, and the socket member 3 toward the shank I.

A centering spring 22 may be frictionally engaged in axial recesses in the inner end of the shank I and the adjacent face of the socket member 3 to urge the socket member 3 into axial alignment with the shank I. Anti-friction balls 23 may be disposed between the inner end of the shank I and the socket member 3 to facilitate radial movement of the socket member 3 under load.

In operation, the shank I may be secured in fixed position, and any desired tool, for example a reamer, may be secured in the tool holder 5. The work may then be rotated and fed towards the tool. Before the work contacts the tool the barrel 2 is loosened so that the shoulder I! is out of contact with the ring I4. In this position the ball and socket joint parts are held together by the spring 2 I, and the tool holder 5 is free to move both angularly and laterally with respect to the ative rotation of the tool holder 5 and the shank axis of the shank I. The tool is started in the work by the operator and is then free to center itself in the work without regard to slight varia- 3 tions between the axis of the work and the axis of the shank I.

As soon as the tool has found its correct position, the operator may secure it in that position and prevent chattering or further movement of the tool by simply screwing the barrel 2 toward the shank I until the shoulder I'I contacts the ring I4 and presses and locks the parts together. A partial turn of the barrel is normally sufficient to free the tool to hunt its correct center, or to lock the tool in its selected position.

Manifestly, the same general procedure may be followed in the event it is desired to rotate the tool instead of the work. When the holder is used in this manner it may be rotated in the direction to screw the shank I into the barrel 2, so that retarding the rotation of the barrel causes the parts to be screwed together to lock the tool in its selected position.

In the modification shown in Fig. 3, the shank 25 is threaded into the barrel'ZG. The tool holder 21 is formed with a ball 28=bearing against a socket member 29, and'with'a reduced bifurcated extension 30 which enters acentral recess 3| in the shank 25. Relative'rotationof the shank 25" and the tool holder 21 ispreventedby a-pin 32 extending across the recess 3I- and passing through the slot 33 between the bifurcationsof theextension 30. The 'pin 32 is smaller indi'ameter than thewidth of the slot 33; and the extension 30 is smaller than the recess-3|, so that the tool holder 21 may move laterally and angularly' with respect to the shank'25-inall directions.

The socket member 29 is smaller in diameter than the interiorof the barrel 26; so thatit may move radially in all directions with respect to'the shank 25. may be disposed between the'socket member 29* and the inner end of the shank 25 to facilitate such movement.

A ring 35, corresponding to the ring II in Fig. 1, engages the ball 28 adjacent the shank of the tool holder 2?, and is smaller in diameter than the interior of the-barrel 26 to permit radial movement of the ring. The barrel 26 is formed with an inturned flange 36*adaptedto engage the front face 31 of thering 35 when the barrel is screwed down so as to lockthe parts'in' their selected position in the-samemanner as describedin connection'with Figs. land 2. Spring pressureto hold the parts together when the barrel is loosened may be provided by balls 30 slidably mounted in holes 39 in-the'flange 36" and urged against the ring 35 by springs 40. The operation of this form of the invention is" substantially the same as the operation of the form shown in Figs. 1 and 2 and described above.

In the modification shown in Fig. 4, a shank IN is screwed into one end of a barrel I02. The inner end face of the shank IOI is formed with an axial bore I03 which servesas a socket mem-' ber to receive the ball I04; Adjacent the bore I03 the end face of the-shank I-I is formed with projectin lugs I I0; A tool holder I is provided with a socket member I06 on its inner endto engage the ball I04; The socket member I06 is formed with notches III to receive the lugs I I0. As in the embodiment shown in Figs; 1 and- 2, the lugs I II! are narrowerandshorter-than the notches I II to permit universal annular movement of the tool holder I05 with respect to the axis of the shank IOI. The ball I04 is smaller in diameter than the bore I03 so that the ball I04- may move laterally in all directions with respect to the axis of the shank IO-I. As shown in Fig.

If desired, anti-friction bearings 34 4 4, the spherical recess H2 in the socket member I00 which receives the ball I04 may be curved on a slightly greater radius than the radius of the ball I04, so as to permit freer movement of the ball I04 radially with respect to the socket I03 in any direction. This relationship of the recess H2 and the ball I04 also permits further angular movement of the holder in the event the ball should be offset radially to the limit of its movement in the bore I03, and reduces the friction of the parts, particularly when the shank is rotated and the ball I04 is offset radially from the axis of the shank Hill.

The socket member I06 is formed on its outer face with a convex, substantially spherical surface II3, preferably concentric with the surface of the ball I04. A ring II4 surrounds the socket member II'6 and is formed with a concave, substantially spherical surface II5 engaging the surface I I3. The opposite face H6 of the ring I I4 engagesa shoulder II! on the interior ofthe barrel 2. As in the form shown in Figs. 1 and 2- the ring H4 is smaller in diameter than the interior of the barrel I02, permitting universal radial movement of the ring with respect to the barrel, and the shoulder HT is preferably of suchlength as to remain in contact with the face I I6 of the ring in all positions of the latter.

The barrel I02 is-also formed with a counterbore- I'IB'terminating in an inturnedflange H9 and a retainer ring I20 held in place by a spring' I2I- is providedto close the opening in the end of the barrel I02 without interfering with the universal movement of the tool holder I05, in the same manner as disclosed in Figs. 1' and 2. The spring I2I also urges the joint parts together when the shoulder III isout of contact with the ringl I4;

The operation of the device shown in Fig. 4 is substantially the same as the operation of the embodiment shown in Figs. 1 and 2 except that lateral offset of the tool holder I05 in all direc' tions with respect to the axis of the shank I-0I is permitted by movement of the ball I04 in therecess I03 instead ofby a separate socket member engaging the end of the shank IN.

The modification shownin Fig. 5 is substantially identical with the embodiment shown in Fig. 4 except that instead of aseparate ball I04- the tool holder 205 is formed with an integralextension 204 having a spherical surface engaging the bore 203in the end face of the shank 20I, The spherical surf'aceof the projection 204 is free to move radially in all directions within the bore 203 to permit lateral ofiset of the tool holder 205' with respect to the axis of the shank 20 I. In other respects the operation of the embodiment shown in Fig. 5 is-the same as that shown in Fig. 4.

The embodiment of the invention shown in Fig. 6 is similar to theembodiment shown in Figs. 1 and 2 except that the centering spring I4 is omitted and a central bore isextended through the entire assembly to accommodate tool shanks ofunusual length. In this form the shank 30lis provided with an axial bore 34I greater in diameter than the axial bore 342 in the tool holder 305. Thus a tool with an unusually long shank maybe secured in the tool holder 305 and the end of the shank may extend into the bore 34I. Manifestly thediameters of the openings may be such as to permit any desired degree of movement of the tool holder 305 laterally and angularly with respect to the axis of the shank 30I.

A socket member 303, smaller in diameter than the interior of the barrel 302-, is arranged for radial movement in all directions against the end face oi the shank 30!. The tool holder 305 is formed with an integral projection having an annular spherically curved surface 304 engaging a corresponding recess in the face of the socket ember 353. The socket member 303 is formed with a transverse rib 30'! extending into a transverse slot 305 in the end face of the shank 30 l, the Si l being narrower than the slot 309 as in the embodiment shown in Fig. l. The socket member 303 also has lugs 3l0 extending into notches til i in the head 306 of the tool holder 305. The lugs .tlll are narrower and shorter than the notches til to permit universal angular movement of the tool holder 305. The ring 3M engages the convex spherical surface 3 l3 on the tool holder 395 and is engageable by the shoulder 3!? in the barrel 302 as in the embodiment shown in 1 and 2. If desired, anti-friction balls 323 may be disposed between the socket member 303 and the face of the shank Sill to facilitate radial movement of the socket member 303. The socket member tilt is also formed with an axial bore 343 which may be of the same diameter as the bore t ll so as to permit passage of a long tool shank without interfering with the universal movement of the tool holder 305. In other respects the construction and operation of the form shown in Fig. 6 are the same as in the embodiment shown in Figs. 1 and 2.

In all the embodiments shown it will be seen that the tool holder is free for universal movement both laterally and angularly with respect to the axis of the shank when the barrel is loosened so that the parts are held together only by spring pressure. In each embodiment the tool holder may be locked in any selected position with respect to the shank by simply screwing the barrel down against the joint. The locking of the parts in position does not exert any forces tend ing to alter the selected position of the tool holder either laterally or angularly with respect to the shank. Thus a tool held in the holder of any of the embodiments shown may be permitted to hunt its own position of alignment with the work when being started, and then by a simple tightening of the barrel may be locked in the selected position so as to continue its work without chattering or further movement.

Although several embodiments of the invention have been described in considerable detail it will be understood that many variations and modifications be resorted to without departing "rom the scope of the invention as defined in the following claims and similarly that many of the features shown in the various embodiments may be incorporated in the other embodiments when desired.

I claim:

1. A universal floating tool holder comprising a shank element and a tool holder element, con vex abutment means associated with and between said elements and arranged to provide for relative angular and lateral motion of said elements, interengaglng driving means associated with said elements and arranged to rotatably couple said elements while providing for said relative angular and lateral motion, said tool holder element having a wall portion facing generally axially away from said shank element and lying in a sphere whose center is that of said pivotal motion, a generally radial flange element having a radial wall portion facing said tool holder Wall portion, an annular washer between said wall portions and having a radial face and a spherical face complementary to the corresponding wall portions whereby the plane of lateral motion is perpendicular to the axis of the shank element, and sleeve means extending between said generally radial flange element and said shank element, said sleeve means being threaded to one of said last named elements in order to draw them together, said annular washer providing for clamping said shank and tool holder elements together in any adjusted position.

2. universal floating tool holder comprising a shan element and a tool holder element, con 1.1eans associated with and between ring means associated with said elements and arranged to rotatably couple said elements while providing for said relative angular and lateral motion, said tool holder element having wall portion facing generally axially away from said shank element and lying in a sphere whose center is that of said pivotal motion, a gem erally radial flange element having a radial wall portion facing said tool holder wall portion, an washer between said wall portions and having a radial face and a spherical face complementary to the corresponding wall portions whereby the plane of lateral motion is perpendicular to the axis of the shank element, sleeve means extending between said generally radial flange element and said shank element, said sleeve means being threaded to one of said last named elements in order to draw them together, annular washer providing for clamping said shank and tool holder elements together in any adjusted position, and spring means between said washer and an associated element arranged to urge said elements into intimate frictional engagement.

THEODORE E. FRISCO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 553,265 Scholer Jan. 21, 1896 1,513,647 Spiritus Oct. 28, 1924 1,565,553 Maisch Dec. 22, 1925 1,782,633 Schiltz Nov. 25, 1930 1,907,447 Schlitz May 9, 1933 OTHER REFERENCES Hervig, American Machinist of May 24, 1923, page 773, copy of which is in class 279-16 in Division 52. 

